1. Field of the Invention
The invention relates to devices for transmitting torque from a rotary power source to a driven device and for compensating for misalignment between the power source and the driven device. More particularly, the invention relates to flexible couplings for transmitting rotary power from a rotatable driving shaft to a rotatable driven shaft.
2. Discussion of Prior Art
Flexible torque transmission couplings are commonly used devices for connecting the ends of rotatable driving and driven shafts. The coupling includes a pair of flanked hubs respectively supported by the ends of the shafts. One or more flexible coupling elements are placed between and connected to the hubs, thereby enabling rotation of the driven shaft in response to rotation of the driving shaft. In the event the driving shaft and driven shaft are misaligned, the flexible coupling compensates for such misalignment without the need for repositioning the shafts.
In conditions wherein the ends of the driving and driven shafts are spaced too far apart for the hubs to be connected by flexible coupling elements, a tubular center member having opposite flanked ends is often provided to connect the hub flanges. The center member is connected at its opposite ends to the respective hub flanges by flexible coupling elements.
In conditions wherein the available space between the power source and the driven device is limited, the hubs on the driving and driven shafts may be inverted. In such an inverted hub arrangement, the ends of the shafts are closely spaced, and the flanges of the hubs remain spaced apart. Also, in an inverted hub arrangement, a tubular center member having opposite flanked ends is often provided to connect the hub flanges. The central member houses the respective ends of the shafts and is connected at its opposite ends to the respective hub flanges by flexible coupling elements.
Flexible transmission couplings can be constructed so that the coupling has a capacity to carry maximum torque load between the driving and driven shafts without regard to the direction in which the shafts rotate in common. Couplings having such a capacity are known as "bidirectional" couplings.
It is also known to provide a flexible torque transmission coupling having a capacity to transfer loads of a greater magnitude between the driving and driven shafts when the shafts rotate in common in a first direction than when the driving and driven shafts rotate in an opposite second direction. Such flexible couplings having different maximum torque transmission capacities dependent upon the direction of rotation of the driving and driven shafts are known as having a "biased" torque capacity. Flexible couplings having a biased torque capacity are commonly used in applications wherein the driving and driven shafts are capable of rotating in common in either of two directions and the loading therebetween is expected to be greater during rotation in one direction than in the other direction, and in applications wherein the shafts are capable of rotating in common only in a single direction.